A disclosed apparatus for use with a conduction-cooled card assembly may include a frame comprising first and second thermally conductive portions adapted to engage respective thermal management interfaces on opposite sides of a conduction cooling frame for at least one circuit card. The apparatus may also include a passageway extending between first and second openings in the frame so as to allow cooling fluid to flow into the first opening, through the passageway, and out of the second opening. According to a disclosed method, an insert may be installed between components of a mezzanine connector so as to increase a height of the connector. In some implementations, the installing of the insert may be performed while the first and second components of the mezzanine connector are mounted on a host card and a mezzanine card, respectively, so that installation of the insert between the first and second components increases a spacing between the host card and the mezzanine card.